I own and use several 6x9 folder cameras. Just had a tripod mount break off one, so now that is a shelf item. I managed to do my own repairs on these, unsticking the front lens element, cleaning and adjusting the shutters, and replacing the bellows with some NOS items trimmed to fit. The source folder cameras I started with were AGFA or Ansco folder cameras, several with a limited Vario shutter, and one with a Compur Rapid shutter. The Vario and Pronto shutter versions are the simplest and cheapest, with many working fine after a little exercise. The Prontor multiple speed shutters are complicated to get working nicely, and Compur shutters involve close to the same difficulty level, though both tend to hold up quite well except at the fastest settings. The shutters from many 6x6 or 6x4.5 folder cameras of the same era sometimes are exchangeable, though the lenses will not generally cover 6x9. Always a good idea to have spares or extras when working on these.
Frozen front focusing lens group/elements seem to be all too common. I use a Sorathane rubber pad, 99% alcohol and gentle force with an art eraser to work these apart. Some old lubricant hardens and becomes like glue. A common mistake some people can find with a folder is that the entire front elements can turn in the mounting, rather than the front element actually moving to focus. The three element lenses are the easiest to work on, especially most of the AGFA, Ansco, or Balda folders. Most three element folder lenses focus by moving the first element closer or further from the second element. The third element is on the back of the camera, inside the bellows. On many of the simpler and lower cost AGFA, Ansco, or Balda 6x9 choices, the lens elements are located and not glued in place. This makes disassembly, cleaning, and reassembly easier, if you want to tackle this repair.
Bellows usually leak light, and are easy to confirm with a flashlight shining through the bellows from inside the camera (try in dark room to make this easier). Replacement bellows are tough to find, though I got lucky with this item. Old leather bellows seem to hold up better than the more plastic bellows. I use ink for screenprinting (as in T-shirt printing) as a patch material, though there are numerous other methods and materials. If you try too thick a repair material, or something that does not flex, you can have problems like not being able to close the camera, or the repair flaking off (sometimes inside the camera).
So if you want to try repairing a low cost folder, my suggestion is to buy two or three as spare parts. You can find lots of these on EBAY at really low prices; despite claims by many of working cameras it might be easier to assume a really low cost camera will not work properly. There are a few more expensive repaired or restored cameras on EBAY, so that is another option, and often only around two or three times what it could cost to do the repairs on your own.
I found a funny issue on film flatness. Many of these folder cameras can pop open when triggering the clamshell release button. If you let it fly open, and the bellows is not full of holes, then the negative pressure can suck the film partially into the film gate. Open the clamshell slowly and in a controlled manner to avoid this problem. Besides that, it is a big area of film, though can produce some surprisingly nice image results. I have run transparency films through mine, and had very nice large prints made from those images, so your contact printing should work very nicely.
I don't think you should spend lots of money on these, since even the cheap items can produce nice images when they are working as they should. If you have never done a repair on something this small, or not sure about trying that route, then spend a little more to buy a working folder from someone. Most of all, have lots of fun using these.
Ciao!
Gordon
But one of the best things about folders is, they are so cheap and portable you can keep one for color and one for black and white and carry both with you at no bother at all. 
